Arduino Snap Circuit siren controller

1#define R1 6
2#define R2 7
3#define R3 9
4#define R4 8
5
6
7void  setup() {
8 pinMode(R1, OUTPUT);
9 pinMode(R2, OUTPUT);
10 pinMode(R3, OUTPUT);
11  pinMode(R4, OUTPUT);
12
13digitalWrite(R1,HIGH);
14digitalWrite(R2,HIGH);
15digitalWrite(R3,HIGH);
16digitalWrite(R4,HIGH);
17
18
19}
20
21void  loop() {
22  // put your main code here, to run repeatedly:
23digitalWrite(R1,  LOW);
24delay(3000);
25digitalWrite(R1, HIGH);
26
27digitalWrite(R2, LOW);
28delay(3000);
29digitalWrite(R2,  HIGH);
30
31digitalWrite(R3, LOW);
32delay(3000);
33digitalWrite(R3, HIGH);
34
35delay(4000);
36
37digitalWrite(R2,  LOW);
38digitalWrite(R1, LOW);
39delay(3000);
40digitalWrite(R1, HIGH);
41digitalWrite(R2,  HIGH);
42
43digitalWrite(R2, LOW);
44digitalWrite(R3, LOW);
45delay(3000);
46digitalWrite(R2,  HIGH);
47digitalWrite(R3, HIGH);
48
49digitalWrite(R1, LOW);
50digitalWrite(R3,  LOW);
51delay(3000);
52digitalWrite(R3, HIGH);
53digitalWrite(R1, HIGH);
54
55
56digitalWrite(R1,  LOW);
57digitalWrite(R2, LOW);
58digitalWrite(R3, LOW);
59delay(3000);
60digitalWrite(R3,  HIGH);
61digitalWrite(R2, LOW );
62digitalWrite(R1, HIGH);
63
64digitalWrite(R3,  LOW);
65digitalWrite(R1, LOW);
66delay(3000);
67digitalWrite(R1, HIGH);
68digitalWrite(R3,  HIGH);
69
70delay(3000);     
71
72
73
74
75}